I'm in Palm Springs,CA and we had a forest fire in the mountains that dropped a lot of ash in the pool...and everywhere....Now my filter cartridges seem to be getting clogged up even two hours after cleaning. They were making it several weeks between cleanings....Do I need to replace them? Is there something I can do to get them cleaner?

Safety first - make sure you have long pants and sleeves on - rubber gloves and some goggles too!!

Get a plastic container tall enough to submerge the whole filter (trash can usually works pretty good). Fill the container with about 2 gallons of muriatic acid and the rest water. Carefully place the filter in the container. You should see the filter fizz and bubble within a minute or 2. Let it soak for at least 24 hours. Give it a very thorough rinsing and put it back in the filter. This should improve the performance of the filter. If it doesn't, you most likely need to replace the cartridge.

Fire ash is the worst. I still remember the San Diego fires and the destruction it caused.

Pool filters will clog up in nothing flat, as you are finding out. The best way to get the ash out is the use a Flocculant, let the dust settle and with a portable vacuum pump, vacuum the pool. Let the water discharge into the sewer(I imagine Palm Springs is very strict about waste discharge). Then refill your pool and let the filter clear up the pool.